Question

the speed of boat in still water is 20 m/s and speed of flowing water in river is 10 m/ s .Find out minimum time in which river can be crossed. Also with what angle which flow of water should be driven so that it cross the river in shortest path ( width of river =500 m)​

Answer 1

Answer:

Minimum Time = 25 s and theta = 30

Explanation:

For minimum time,

t=d/velocity of boat

= 500/20

= 25 s

For shortest path angle theta =

Sin theta = Vel of river / Vel of man

               = 10/20

               =1/2

Theta = 30 or $\pi$ / 6